Non standardisation / Incompetency

I recently went to the Vodacom Store in Galleria to upgrade a business contract to the new Unlimited Contract. On my first visit there, I inquired about the requirements for the upgrade in terms of paperwork, letter head, ID etc. Second visit I had taken all the required information and wrote out the letter on the official company letter head as per the instructions of the Vodacom Staff member. This letter was word for word as per the Vodacom Staff members instructions. I was thereafter issued with 3 sim card as per the contract benefits. A week passed and I noticed that one of the three sim cards issued was not activated. So I visited the store for the third time to get it activated. They inform me that cannot find the original letter submitted and should forward my copy of the letter to have it activated. I put up fuss but sent through the scanned copy of mine. After receiving the letter they refuse to activate the sim because the letter is insufficient and requires more details and I must submit another letter before they can activate the sim card. This is ridiculous. Do I have to keep submitting letters until they get it right???